nothrow functions/methods

[Daniel Murphy]

bearophile Wrote:

> Before filing a possible bug report I prefer to ask here, because my ideas are often wrong.
> This is a small D2 program:
> 
> nothrow void foo() {
>     // auto a = new int[5]; // not allowed here
>     int[int] aa;
>     for (int i; i < 100_000_000; i++)
>         aa[i] = i;
> }
> void main() {
>     foo();
> }
> 
> Inside that function foo() you can't put a "new int[5]" I presume because it can throw a memory overflow exception. But then why are insertions into an associative array allowed? Can't they produce the same memory overflow exception? In theory nothrow functions can forbid adding new items to associative arrays.
> 
> 
> [Related: In Python stack overflows are normal exceptions that you can catch, etc. But I presume it's OK for nothrow functions in D2 to not refuse the possibility of a stack overflow error, because essentially all D2 functions can produce stack overflows, if before calling them the stack was filled up.]
> 
> Bye,
> bearophile

Allocations are allowed inside nothrow functions.  If I remember correctly, the reasons are that disallowing them would limit usefulness, and that OutOfMemoryError is not generally recoverable.